Improvement in hydraulic elevators



M. L.. WYMAN.

HYDRAULIC ELEVATOR.

110.174.171. Patented Feb. 291, 187e. 'l

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. UuIrEu4 STATES MARTIN` L. wrMnu, or Bosr'oM-MAssAcHUsE'rrs, AssIGNoR To HIM AND. cHARLEsE. MOORE, or SAME PLAGE.

'PA'rnNT OFFICE.

IMPRovEMi-:NT IN HYDRAULIC'en evAToRs.`

Specification forming part of Letters Patent'No. 174,171, dated February 29, 1876; application led July 15, 1875. y

' To all whom it may concern Be it known that I, MARTIN L. WYMAN, of

Boston, in the county of Suffolk andState of water or other liquid employed will bel govern ed by the .weight of the car and its load, or the work .being performed and', also, in the combination Aof such piston .andcylinder of valves, 4as hereinafter'specitied, whereby theV passage of the lwater through the cylinder is controlled.

Figure l represents a side view of sufficient of an elevator to show my presentV improvement, and Fig. 2 is a topview thereof.

The car a., of any suitable size or kind, is guided by the guide-rails I), or in any wellknown way, and is raised and lowered through the agency of a suspensory rope orchain, c, or ropes leading over pulley d, and wound on the windingdru1n c, suitably connected with shaft vj', supported in bearings' g, the shaft being provided with smaller drums h, to which are attached ropes i, connected with the crosshead j, carried by the piston l, the latter being arranged within the cylinder m, and being fitted to move through a stuffing-box of any well-known construction made in the cylinder head n, the piston-head o fitting the interior of the cylinder. This piston l is sufficiently large in diameter to occupy a space equal to about one-half the capacity of the interior ofthe cylinder m, and the piston-head o has a valve, 19, made to swing or open away from that head of the cylinder through which the piston l works, the way or passage q, covered by the valve p, leading through the piston-head o, and into the water-space r about lthe piston Z. The inlet-valve is lettered s, and there are two outlet-valves, t and a, the former being situated at the end of the cylinder, and connected with the drain, while the valve u is connected with the top of the cylinder, as hereinafter described. This valve u is a three-way valve or stop of ordinary v construction, and the valves or stops s t are such as are ordinarily employed'with hydraulic elevators, and they are all controlled through a hand-rope by the operator of the car as the car moves,l so as to open and close the said valves or stops, as may be required. This hand-rope for operating the valves being commonly employed on elevators is not herein shown. The ropes or bands c', two ormore, areadapted to lead from the cross-head j, under and about the drunis h,.and the hoisting-ropeor suspensory, one or more, leading under the drum e from the opposite direction, so that one set of ropes winds up, while the other unwinds, and vice versa. Assuming the car down, and all the valves or stops closed, then to cause the car to ascend with a heavy load, pull on the hand-rope and open inlet-valve s and outlet-valve t, and the water, acting against the large piston-head, will push out the piston, and,V through the ropes 'i and shaft and suspensory, the car will be raised. The car may bestopped at any place by closing valves. When the car is to descend. the stops or valves s t are closed, the valve u is opened, and the weight of the car, drawing o n the suspensory, and acting through theshaftf, ropes i, and piston, causes the piston to move into the cylinder, and the water passes out through the valve u.

Now, instead of wasting all the water con-A tained between the -piston-head and the end w of the cylinder, I connect with the three-way stop u and the cylinder a saving-pipe, a', its

end opposite from the valve or stop u opening into the cylinder back of the piston-head o, and about one-half the water in advance of the piston-head Hows through such saving pipe into the space r back of the piston-head and about the piston, and the remaining portion of the water is forced through the stop or valve u into the drain, and is wasted. The car descends until at the point where it is desired to have it rest, then all the valves are again closed.` Now, as the car is to ber again elevated, if the load is light, less force or power is needed to elevate it than if the load were heavy, and consequently a small quantity of water will suffice to .elevate the car, if a small quantity can be used. This small quantity of water, can be used, and in the fol- SELF I lowingway; The loadz being light, vonly the*k inlet-valve s will be openedand as 1the'pls'tonA is moved back'by the'water coming into' thev inlet, the water before led into space r by the saving-pipe a when the ear descended, (suchl space being; equal to about half lthe capacity of the cylinder,) having no outlet,fforcesthe valve p in the head o open, as shownin dotted lines, and the Water in space r passes into the space in front of the piston-head, and is saved,

and as the car again descendsl the ,valve-uds'.

opened, and about onehalt' the Water in front of the head o is again returned to the space T through-pipe a', andin-this way a'large quantity of Water is saved, especially when the elevator-car is not being worked to its full capacity, as is oi'ten the case.

If, however, the load should be heavy,then thevvalve t is opened, whenpistonl starts back, which gives to thecylinder .its fnllcapacity, and water in the space r will pass` through valve t into the drain.

I may employ other well-known connections between the piston and the caninstead .of those shown, but I prefer those shown, the gist of this invention being in the provision for controlling the Water according to the.,

ofthe three-way stop,I :it being placed by a. hand-'ropelin `proper-position forthat purpose.' It is, of oourse,understood that instead offthc' three-way stop, and the other stops shown, I may Yuse-poppet or other well-known valves to open and close, as and in the times described,

passages foru the loW-o'f theavaterfasset forth.4

I claim- 1. The combination, in an hydraulic eleva tor, ofthe cylinder, piston, and valved pistonhead, .adaptedtoy allow the water in the cylinder back. of the piston-head to pass into the cylinder in front of the piston-head, substantially as described-.f v

2; The combination, with the cylinder and piston, provided With a head and valve therei in,- of a stop or valve and saving-pipe adapted to lead the'water in advance of the pistonvhead back into the cylinder, substantially as, and for the purpose described.

8.. vThe combination, with the cylinder, inletvalve, two outlet-valves, and savingpipe, of a piston and head, provided with a valve, 'and l. adapted tot operate substantially as and for'y the purpose described.

.4.' The combination, Witlitlie cylinder and valved piston,stop or valve u, and connected.'

saving-pipe, of the cross-har, ropes i, shaftl f,

drumsh e, suspcnsory and car, substantially as described. l

In testimony whereof I havef signed my name to this specification in the presence of two-subscribing witnesses.

MARTIN L. WYMAN'. Witnesses:

G. W'. GREGORY, L. H. InyrnicrER.` 

